1. Field of the Invention
The present invention relates to an image forming system configured from a data communication apparatus that transmits electronic mail data generated based on facsimile data received via a public line and an image forming apparatus that forms an image based on that electronic mail data.
2. Description of the Related Art
Conventionally, an image forming apparatus that has a facsimile function for transmitting and receiving facsimile data via a public line has been generally known. Further, in recent years Internet facsimile apparatuses (hereinafter sometimes also referred to as “Internet FAX apparatus”) have been also becoming commonplace as a facsimile apparatus capable of performing facsimile communication via the Internet using an electronic mail protocol. An Internet FAX transmits data by using an electronic mail protocol (simple mail transfer protocol (“SMTP”)) instead of a telephone line, and is recommended by the International Telecommunication Union (ITU).
An Internet FAX apparatus can utilize the Internet or an intranet to transmit and receive a facsimile. Compared with a facsimile apparatus that utilizes a telephone line, an Internet FAX apparatus can realize a reduction in communication costs, can computerize paper documents by a simple operation equivalent to a facsimile, and can attach that computerized document to an electronic mail and transmit it to a personal computer. Under an Internet FAX apparatus standard called “simple mode”, image data with an A4 printing paper size and 200 dots per inch (dpi) printing resolution can be transmitted from the Internet FAX apparatus to a printer, and the image data received by the printer can be printed out.
Further, the above-described image forming apparatus can also receive and print out electronic mail other than electronic mail transmitted based on the Internet FAX standard. Moreover, in addition to the electronic mail receiving function, the above-described image forming apparatus may include a function for printing print data generated by a printer driver on a personal computer (PC) received via a network. Such a printer can also print electronic mail and page description language (PDL) data received in parallel.
Japanese Patent Application Laid-Open No. 2002-64670 discusses a FAX apparatus that restricts printing when a toner remaining amount is less than a predetermined value in order to prevent a print product from becoming faint due to lowering of the toner remaining amount.
When printing the received PDL data, although printing can be repeated by re-transmitting the data from the PC, if the received data is electronic mail data, since the sender and the receiver are different, in many cases it is impossible for the receiver to re-transmit and print the data.
Consequently, if printing is prohibited across the board regardless of the type of data when the toner remaining amount falls below the predetermined value as carried out in the conventional method, when receiving and printing the print data, printing is restricted despite the fact that a few pages can be printed even though the toner remaining amount has fallen below the predetermined value. Consequently, user convenience is dramatically reduced.